Question

我以前在DataGrid中有一个继承自DataGridColumn类的类。这允许我创建一个复选框列，标题中包含客户端un / check-all框。然后，当我设计我的网格时，我只想添加我的自定义列。

我目前正处于一个需要网格视图类似功能的项目中，但似乎没有办法继承或添加功能到列。

所以我的问题是，有没有办法覆盖列？或者这个代码是否已经以可重用的方式存在？

需求很简单：我希望它只是在页面上注册JavaScript并呈现一列复选框。

我已经遇到过4guys示例，但他们刚刚将所有代码放入代码中，我正在寻找一些不那么复制/粘贴的东西。

Answer 1

我从System.Web.UI.WebControls.BoundField和.HyperLinkField派生了类您可能有兴趣继承CheckBoxField类http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.checkboxfield.aspx

Answer 2

您可以在DataGrid列中使用包含CheckBox的ItemTemplate的TemplateColumn吗？

类似的东西：

<asp:DataGrid id="DG1" runat = "server" DataKeyField = "ID">
<Columns>
<asp:TemplateColumn HeaderText="ProductName">
<ItemTemplate>
<asp:CheckBox id="chkBox1" runat="server" 
Text =<%# DataBinder.Eval(Container.DataItem,"yourDataToBind") %>
checked='<%# DataBinder.Eval(Container.DataItem,"yourBoolToBind")  %>'>
</asp:CheckBox>
</ItemTemplate>
</asp:TemplateColumn>
</Columns>
</asp:DataGrid>

Answer 3

我继承了BoundField并想出了这个：

页码：

<%@ register tagprefix="CAC" namespace="UI.Controls" assembly="UI.Controls" %>    
<asp:gridview id="grdPrint" runat="server" autogeneratecolumns="False">
    <columns>
        <cac:checkallcolumn />
        <asp:boundfield datafield="CompanyName" headertext="Company Name" />
    </columns>
</asp:gridview>

这是控件：

Imports system.Web.UI
Imports system.Web.UI.WebControls

Public Class CheckAllColumn
    Inherits BoundField

    Public Sub New()
        MyBase.New()
    End Sub

    Public ReadOnly Property SelectedIndexes() As List(Of Int32)
        Get
            Dim selectedIndexList As New List(Of Int32)
            Dim grdParent As GridView = CType(Me.Control, GridView)
            For Each item As GridViewRow In grdParent.Rows
                Dim chkBox As CheckBox = CType(item.FindControl("checkboxCol"), CheckBox)
                If ((Not (chkBox) Is Nothing) _
                            AndAlso chkBox.Checked) Then
                    selectedIndexList.Add(item.DataItemIndex)
                End If
            Next
            Return selectedIndexList
        End Get
    End Property

    Public ReadOnly Property SelectedDataKeys() As Object()
        Get
            Dim dataKeyList As ArrayList = New ArrayList
            Dim grdParent As GridView = CType(Me.Control, GridView)
            If (grdParent.DataKeys.Count > 0) Then
                For Each selectedIndex As Int32 In SelectedIndexes
                    Dim DataKey As Object = grdParent.DataKeys(selectedIndex).ToString
                    dataKeyList.Add(DataKey)
                Next
            End If
            Return CType(dataKeyList.ToArray(GetType(System.Object)), Object())
        End Get
    End Property

    Public Overrides Sub InitializeCell(ByVal cell As DataControlFieldCell, ByVal cellType As DataControlCellType, ByVal rowState As DataControlRowState, ByVal rowIndex As Integer)
        If cell Is Nothing Then
            Throw New ArgumentNullException("cell", "cell is null.")
        End If
        MyBase.InitializeCell(cell, cellType, rowState, rowIndex)
        If (cellType = DataControlCellType.Header) OrElse (cellType = DataControlCellType.DataCell) Then
            Dim checkbox As CheckBox = New CheckBox
            If cellType = DataControlCellType.Header Then
                checkbox.ID = "checkboxHead"
            Else
                checkbox.ID = "checkboxCol"
            End If
            cell.Controls.Add(checkbox)
        End If
    End Sub

    Public Shared Sub RegisterClientCheckEvents(ByVal pg As Page, ByVal formID As String)
        If pg Is Nothing Then
            Throw New ArgumentNullException("pg", "pg is null.")
        End If
        If formID Is Nothing OrElse formID.Length = 0 Then
            Throw New ArgumentException("formID is null or empty.", "formID")
        End If
        Dim strCol As String = GetCheckColScript()
        Dim strHead As String = GetCheckHeadScript()
        If Not pg.ClientScript.IsClientScriptBlockRegistered("clientScriptCheckAll") Then
            pg.ClientScript.RegisterClientScriptBlock(pg.GetType, "clientScriptCheckAll", strHead.Replace("[frmID]", formID))
        End If
        If Not pg.ClientScript.IsClientScriptBlockRegistered("clientScriptCheckChanged") Then
            pg.ClientScript.RegisterClientScriptBlock(pg.GetType, "clientScriptCheckChanged", strCol.Replace("[frmID]", formID))
        End If
        RegisterAttributes(pg)
    End Sub

    Private Shared Sub RegisterAttributes(ByVal ctrl As Control)
        For Each wc As Control In ctrl.Controls
            If wc.HasControls Then
                RegisterAttributes(wc)
            End If
            If TypeOf (wc) Is CheckBox Then
                Dim chk As CheckBox = DirectCast(wc, CheckBox)
                If Not chk Is Nothing AndAlso chk.ID = "checkboxCol" Then
                    chk.Attributes.Add("onclick", "CheckChanged()")
                ElseIf Not chk Is Nothing AndAlso chk.ID = "checkboxHead" Then
                    chk.Attributes.Add("onclick", "CheckAll(this)")
                End If
            End If
        Next
    End Sub

    Private Shared Function GetCheckColScript() As String
        Dim strScript As String
        strScript = " <script language=JavaScript>"
        strScript &= " function CheckAll( checkAllBox )"
        strScript &= " {"
        strScript &= " var frm = document.[frmID];"
        strScript &= "  var ChkState=checkAllBox.checked;"
        strScript &= "  for(i=0;i< frm.length;i++)"
        strScript &= "  {"
        strScript &= "         e=frm.elements[i];"
        strScript &= "        if(e.type=='checkbox' && e.name.indexOf('checkboxCol') != -1)"
        strScript &= "            e.checked= ChkState ;"
        strScript &= "  }"
        strScript &= " }"
        strScript &= "  </script>"
        Return strScript
    End Function

    Private Shared Function GetCheckHeadScript() As String
        Dim strScript As String
        strScript = "<script language=JavaScript>"
        strScript &= "function CheckChanged()"
        strScript &= "{"
        strScript &= "  var frm = document.[frmID];"
        strScript &= "  var boolAllChecked;"
        strScript &= "  boolAllChecked=true;"
        strScript &= "  for(i=0;i< frm.length;i++)"
        strScript &= "  {"
        strScript &= "    e=frm.elements[i];"
        strScript &= "  if ( e.type=='checkbox' && e.name.indexOf('checkboxCol') != -1 )"
        strScript &= "      if(e.checked== false)"
        strScript &= "      {"
        strScript &= "         boolAllChecked=false;"
        strScript &= "         break;"
        strScript &= "      }"
        strScript &= "  }"
        strScript &= "  for(i=0;i< frm.length;i++)"
        strScript &= "  {"
        strScript &= "    e=frm.elements[i];"
        strScript &= "    if ( e.type=='checkbox' && e.name.indexOf('checkboxHead') != -1 )"
        strScript &= "    {"
        strScript &= "      if( boolAllChecked==false)"
        strScript &= "         e.checked= false ;"
        strScript &= "      else"
        strScript &= "         e.checked= true;"
        strScript &= "      break;"
        strScript &= "    }"
        strScript &= "   }"
        strScript &= " }"
        strScript &= " </script>"
        Return strScript
    End Function
End Class

GridView复选框列

3 个答案: